Bamboo Backed Ipe (PICS now on page 2)

[BEN]

Hey guys, I'm trying again........
I'm trying a Bamboo backed Ipe bow with some slight R/D. right now its 65 3/4" tip-tip and i've got an Osage handle glueing up right now.
Any concerns or tips as far as tillering?
This is the second time for this bamboo strip. Last week, I was tillering and thought I had it going good. However, when I put a short string on it to try it out, the bottom limb just kept right on curving and wuold have surely broke if I would have tried to draw it back. So.....i cut off and sanded down the bamboo backing and started with another piece of Ipe. Now that I'm back to getting ready to tiller----need some advice.   I DID floor tiller the Ipe before glueing up the handle......

Ben

[BEN]

I forgot......the limbs are 1 1/4" at widest point and taper down to 1/2" tips....
I'm gonna use the same handle design that I used for my wife's bow---the rock viper backed hickory bow I posted here.........

ben

[bigcountry]

Just out of curiosity, was the core about the same thickness on the top compared to the bottom where it started curving?  Or you think it was a weak section?

[Pat B]

You can make what you want with what you have to work with. Boo and ipe are a great combo. After you get it tillered out, narrow the tips to 3/8" or less to reduce tip weight. You could also add a "power lam" between the backing and belly, at the handle to insure a stiff handle.
  I have a few boo backed and hickory backed bows that have become tri-lams because of operator error!

[BEN]

I think it was a weak section......thickness was pretty even, tiller was even with the tillering string---but boy did it develope a wicked curl all of a sudden when I put on the short string.

Pat----rookie question: What is a power lam?
Also, if I narrow the tips , do I need to re-taper the entire limbs or just the tips?

ben

[bigcountry]

I put a power lam in my IPE/Boo bow.  Its a piece of wood that fits between your boo and core at the handle section and usually extends 1/2" past the fades.  I did it because I was using 5/8" IPE stock.  And I was worried my handle would not be stiff and pop off my walnut handle section.  If I was using 3/4" IPE stock, I would not have did it.

Some people do it for decoration.  I find the power lam a pain to make as it has to be thin like 1/8" or so, and then gracefully fade down to paper thin.  

On my IPE/Boo I am trying to finish up, I started having gaps between my boo and core at the intersection where the power lam feathers out.  I filled with super glue, and going to wrap with sinew.

[BEN]

OK................got the tiller down even, strung it up and shot it.  Shoots good, however------it's only 37# @ 28". much weaker than I was hoping!  Tomorrow i think I'm gonna pike it and see what happens if I take 2" off each tip. Hoping it will still hold up and at least give me a hunting weight bow.

What is a good thickness of Ipe to start with to get a 60-65# bow out of???  

Thanks again,
ben

[Pat B]

When I make board bows I start with a full thickness 1" board and reduce it until I get the weight I want. I very rarely reduce it first.

[BEN]

Thanks Pat....................I started with a board already down to 1/2" I think and by the time I tapered and tillered it, I was wa-a-a-a-y under my desired weight......i'll try the 1" next time.....

ben

[bigcountry]

On my IPE/Boo bow, I started at 5/8" at the fades and straight tapered to 3/8" tips.  Mine came in at 58lbs@28" with alot of scraping.  Mostly from the fades to midlimb.  

I got my core dimentions from burnie on primitive archer.  So I started 1" wide at the fades and had 6" for the handle, 2" for the fades.  From the fades, I kept it 1" for 4" past the fades.  I then tapered to 1/2 wide tips.  On the belly fades, I kept it 5/8" to the fades, and tapered to 3/8" thick.  Most of my scrapin was at the fades to midlimb.

I was aimin for 52lbs or so, but tiller looks so good at 58lbs, I kept it that way.  I also had trouble where I sanded the nodes to  much and had to wrap them, so tillering was over.  

1/2" at the tips should easily get ya 60lbs.  

I am not a big fan of scrapin IPE, so not sure about the 1".  But I never had 1" IPE stock either.  I get flooring IPE.

[BEN]

Where do you get the flooring IPE?

Also, my bow came out @ 45# after piking 2" off each end and finishing the sanding.  I was wanting a small-game bow anyway---now I don't have to buy one! Besides I don't know anyone else left-handed  :rolleyes:   I'll post some pics after I get it stained and finished.

ALso, thanks for those dimensions---might try them out.....Do you do any R/D with it, or just a straight bow?

ben

[bigcountry]

Just about any flooring store will have IPE flooring.  It comes however tongue and groove, and has slats on the bottom.  So you have to cut or plane off those slats and the t&G.  I then cut down the middle and have two slats.  I myself would rather start out with 3/4" core.  Then I wouldn't put the power lam in.

If you want 2X4 IPE, you have to find an online IPE decking material.  After I cut out rough dimentions, I get it down to exact straight taper with a 6" planer.

I have only done one, and I put in 2" of reflex at the tips only.  I lost 1" of it.  I still have 1" of tip reflex.

Burnie on PA makes IPE/boo bows all the time and he always gets 60-65lbs @28" with those dimensions.  He seems now only to like tri or quad lams.

Next time if youmake your riser right, you could just add a tri lam to the bottom if youkeep your belly dead flat if it comes underwieght.

[Diamondback59]

ben i  bilid sever bow every year  and 90 %  of all my ipe board bows are 1/2  ipe that pleantyy when u add the boo  your also gonna gain a lot  man if ya can get seom pic s of it on here i think i could help  ya out a bit im sure richrd scaffold at richs bowery will tell ya the same thing     all woods are diff i agree with pat  1 in   but not on ipe hah   to dense to hard 1 in in ips is asking for a 140 pound war bow haha  ipe s tough stuff i think you had a bad ipece of ipe i maybe wrong but i went over it twice and thats what i come up with   cuz just from makin  over 200 ipe bow si can constently make em from 40 to 90 #  every easliy with a 1/2 piece of  ipe   good luck  brock

[bigcountry]

Originally posted by Diamondback59:
ben i  bilid sever bow every year  and 90 %  of all my ipe board bows are 1/2  ipe that pleantyy when u add the boo  your also gonna gain a lot  man if ya can get seom pic s of it on here i think i could help  ya out a bit im sure richrd scaffold at richs bowery will tell ya the same thing     all woods are diff i agree with pat  1 in   but not on ipe hah   to dense to hard 1 in in ips is asking for a 140 pound war bow haha  ipe s tough stuff i think you had a bad ipece of ipe i maybe wrong but i went over it twice and thats what i come up with   cuz just from makin  over 200 ipe bow si can constently make em from 40 to 90 #  every easliy with a 1/2 piece of  ipe   good luck  brock

Holy cow, is this reply a joke???

[BEN]

My bow making mentor/ bought a Ipe 4x4 and cut it down into slats----I think he got 6 boards out of it. He had never used Ipe either so this has been a learning curve for him too. He completed 2 that worked out but all 3 of our successful bows are in the 42-47# range........
I'll post some pics inthe next day or so......bad thing is, I already got it staining so may have trouble making out the differences...

[Steve Kendrot]

Ben, how are you tillering for weight? If you take care to ensure you have even bends before you really start drawing the bow beyond a few inches, and are careful to never pull beyond your intended draw weight between each scraping session, you shouldn't have too much trouble making your desired weight. I'm confused as to why you are floor tillering your belly stock before you glue up? Do you just mean you are tapering the limbs? Perhaps you are removing too much wood before you glue it up.

A 3/4" slat is nice because you can leave some belly wood in the handle. By extending your handle fades into the belly wood you can reduce the risk of popping handles off. I've used 1/2 and 5/8 Osage slats with good luck too. Even half inch slats should give you plenty of limb thickness for a hunting weight bow.

[BEN]

Steve,

I floor tillered the core wood because the fella teaching me does it to get the wood starting to bend before he glues to bamboo-------not a good idea? We use a planer or joiner to do our taper and then after glueing up, a drawknife to even up the limbs. I'm thinking we are taking too much off before the glue-up like you're suggesting.....this is the 3rd bow that has come out in the low-mid 40's.
the bow I just finished is only 3/8" ipe at the handle and just about 1/4" at the tips.......

[Steve Kendrot]

Ben. I'm a novice as well, but I haven't had much problem making weight so I'll tell you what I do. I use a planer to taper the limbs before glueing bamboo on. My boards are starting at about 5/8" and I am tapering to about 1/2" at the tips. I guess this helps achieve a more even bend during glue up when using a r/d design. I can attest that it does because I forgot this step on the last bow and it did not retain as much bend coming out of the form as earlier attemps with tapered limbs did. After glueing and cutting to shape with band saw, nothing more agressive than a rasp touches the bow. I suspect the draw knife may be too much tool at that point. I found it difficult to make weight before I started using a scale religiously. Once I've got it floor tillered (after glue-up) using a rasp, I put a long string on it and tiller with a cabinet scraper from there on out. Once it's bending evenly, I get a short string on it and begin weighing the bow, pulling to but never beyond my intended draw weight, after each scraping session. I use a tillering gizmo to ensure even bends as I go.  Hope this helps.

[BEN]

Thanks Steve.............I'm really starting to think the problem has been taking too much wood off too early. i'm gonna find some more Ipe and use alot of the ideas I'm getting on this thread---from dimensions to task sequences-----thanks alot!!

[BEN]

OK...................some pics of finished bow:
45# @ 28"     60" long: